研究了用间接原子吸收分光光度法测定微量S~(2-).在pH=4.5的含S~(2-)溶液中,加入定量过量的Cu~(2+),使其形成CuS沉淀,多余的Cu~(2+)用戊黄原酸钾配合,然后用甲基异丁基甲酮(MlBK)溶剂萃取配合物.不需分离,直接喷雾有机相溶液测定配合铜.S~(2-)的灵敏度为0.01μg/mL/1％,变动系数2.7％. The determination of trace S ~ (2-) by indirect atomic absorption spectrophotometry was studied in this paper. A quantitative excess of Cu ~ (2+) was added to S ~ (2-) solution at pH = 4.5 to form CuS precipitate, Excess Cu 2+ is complexed with potassium pentoxalate and then the compound is extracted with a solvent of methyl isobutyl ketone (MlBK). The organic compound is directly sprayed and the organic phase solution is measured without any separation. The sensitivity was 0.01 μg / mL / 1% with a coefficient of variation of 2.7%.